Actinium crystals unveiled

New radiopharmaceuticals have radiochemistry research heating up. Such drugs are key for targeted alpha therapy, or TAT, a cancer treatment wherein doctors deliver isotopes that emit α particles to tumors, killing the cancer cells. Actinium-225 is one promising isotope for TAT, but its fundamental binding properties have remained largely unknown. Now a team of researchers at Lawrence Berkeley National Laboratory has published the first actinium single crystal structure, revealing the element’s unique bonding behavior ( Nat. Commun. 2024, DOI: 10.1038/s41467-024-50017-5 ). The properties that make actinium-225 attractive for TAT—namely, that it emits a large amount of α radiation and has a half-life of just 10 days—also make it incredibly difficult to study. So lead researcher Rebecca Abergel turned to actinium-227, a slightly heavier isotope with a 22-year half-life. To source the isotope, the scientists plundered a sample of protactinium-231 the lab had inherited in the 1960s. After decades sitting in